Petersen re-assigned to Minor League camp

On Tuesday morning, Bryan Petersen was re-assigned to Minor League camp. The 26-year-old will open the season at Triple-A New Orleans.

In camp as a non-roster invitee, Petersen was in the mix for a reserve spot. A left-handed hitter, he plays all three outfield positions.

Petersen appeared in 15 Grapefruit League games, and he was 1-for-16.

The biggest hit he had, which isn't included in his official Grapefruit League stats because it came in an exhibition against Team Venezuela, was March 5 at Roger Dean Stadium. In the tune-up for the World Baseball Classic, Petersen delivered a walk-off triple.

Miami's toughest competition is in center field, where Justin Ruggiano, Chris Coghlan and Gorkys Hernandez are in the mix. The team is expected to keep two of the three.

Mathis targets early May return to Marlins

JUPITER, Fla. -- Marlins catcher Jeff Mathis, closing in on one month since fracturing his right collarbone, is hopeful to be back in big league games in early May.

Given a four-to-six week recovery prognosis when he was injured on Feb. 23, Mathis realizes it would be pressing it to be back sometime in April.

"I'm hoping I'm definitely rehabbing in April," he said on Tuesday morning. "I'm hoping that the beginning of May, I'm back in a big league game."

Mathis, who turns 30 on March 31, was hurt in Miami's first Grapefruit League game. His collarbone was broken on a foul tip off the bat of St. Louis' Matt Holliday.

An X-ray taken on Feb. 23 showed the break. Saturday will be one month since the incident. On Friday, Mathis will be examined by Dr. Frank Cook, the team physician, and another X-ray will be taken.

"We'll get another picture taken, and we'll go from there," the veteran catcher said. "I've already started moving it, trying to get back some mobility."

Mathis is moving gingerly. He refrains from any movements above his right shoulder and he uses his left hand to greet people, opting not to shake with his right hand.

"I'm moving it a little bit better," Mathis said. "I'm able to grab some things and do some things. As far as up over my shoulder, I'm not there yet. Everything [below the shoulder], I've had some progress."

The Marlins acquired Mathis from the Blue Jays in November.

An eight-year MLB veteran, Mathis broke in with the Angels in 2005, and he spent 2012 with Toronto.

Mathis entered Spring Training as Rob Brantly's backup.

If the Marlins don't seek options outside of the organization, Kyle Skipworth is considered the front-runner to be Miami's Opening Day backup catcher.

Missing a month of Spring Training has been a frustrating experience for Mathis.

"It's starting wear on me a little bit," Mathis said. "I've been around, but not having a schedule. I've got nowhere to be, except for therapy for an hour, and some cardio stuff, as much as I can. I miss being out there on that field."

Extra week of spring benefits injured players

JUPITER, Fla. -- An extra week of Spring Training has its pluses and minuses.

The way Marlins manager Mike Redmond sees it, the added time is good for players who have been out due to injuries.

To the others in the clubhouse, they are just about ready for Opening Day on April 1 at Washington.

"If you ask most of the guys in there, I think they'd tell you they're ready," Redmond said.

The benefit comes to players like Placido Polanco, Greg Dobbs and Justin Ruggiano. All three missed time due to injuries. Polanco has played sparingly due to a strained right oblique. Ruggiano was out with a back injury, and Dobbs dealt with a right calf ailment.

All three were in the starting lineup on Tuesday in Miami's 5-4 loss to the Cardinals at Roger Dean Stadium. Polanco had a two-run single, Ruggiano went 1-for-3 and Dobbs was 0-for-3.

They are expected to play again on Wednesday against the Nationals in Jupiter, and the team is off on Thursday.

"A couple of guys who have been banged up, we need to get a couple of more at-bats," Redmond said. "We feel like we have enough time to get them more at-bats."

In the final week or so, the hope is to get all the regulars as much time as possible.

"That last week, I'd like to play our regular lineup as many days in a row as we can, as we get ready for Opening Day," Redmond said. "I feel like we're close to being ready to go."

LoMo progressing, begins hitting off tee

JUPITER, Fla. -- If his progression stays as scheduled, Logan Morrison could find himself in some sort of game action around April 15.

The Marlins first baseman continues his rehabilitation from right knee surgery.

"By April, I should be running on solid ground," Morrison said.

On Monday, Morrison did some hitting off the tee.

The Marlins and Morrison aren't rushing anything as he recovers from his second surgery on the same knee.

Morrison continues to run on an anti-gravity treadmill.

The Marlins will open the season with Morrison on the disabled list. But he is hopeful to begin playing in Minor League games in the middle of April.

If he is seeing game action by then, a best-case return date to the Marlins would be around May 1.

Casey Kotchman, a non-roster invitee, has had a strong Spring Training, and he is expected to be the Opening Day first baseman.

Worth noting

• Because of Monday's rain-shortened game, several pitchers had to get game action on Tuesday in Minor League games. Steve Cishek and A.J. Ramos each threw in scrimmages on the back fields. Both were scheduled to pitch on Monday. They each worked one inning. Cishek has been working on a changeup this spring, to go with his fastball and slider.

"It's always good to have another weapon," manager Mike Redmond said of the changeup. "He may not need it right now. But I know over the course of time, sometimes you need another pitch. He's a relatively young guy to the big leagues. A lot of guys don't know him. They don't have many at-bats off him. As he continues to get innings throughout the big leagues and faces hitters, it's always nice to have another pitch that somebody hasn't seen in a big situation."

• Kevin Slowey, competing for a rotation spot, will next throw in a scrimmage on Thursday, Miami's scheduled off-day.

Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter @JoeFrisaro. This story was not subject to the approval of Major League Baseball or its clubs.